Circuit testing board



March 5, 1940. 1, v. coLE CIRCUIT TESTING BOARD 2 Shee-ts-Sheet l FiledJune lO, 1939 INVENTOR. fm//f/ au- ATTORNEY.

March 5, 1940. i. v. COLE CIRCUIT TESTING BOARD Filed June lO, 1939 2Sheets-Sheet 2 INVENTOR. [Rw/v6 alf ATTORNEY.

Patented Mar. 5, 1940 UNITED STATES PATENT OFFICE 11 Claims.

'I'his invention is directed to testing devices, more particularly to adevice whereby testing meters or the like may be introduced into acircuit without interrupting the same at any time.

In certain instances, it is highly desirable to be able to introduce aspecial meter into a circuit for the purpose of testing the consumptionin said circuit. This applies, for example, to a case where in anapartment house there are a considerable number of users of electricity.In some such cases, none of the current is metered to the individualtenants and it becomes desirable to be able to introduce into each ofthe individual circuits a test meter for a relatively short time.However, in so doing, it is essential that the current be notinterrupted even for a small fraction of a minute, as such aninterruption might interfere with the operation of electrical devices inthe circuit, such as an electric clock and the like.

In view thereof, it is among the objects of the present invention toprovide a device which is simple in construction, readily installed,and, which is capable of allowing the introduction of a meter into thecircuit with dispatch and convenience and without interruption of thecurrent.

It is also among the objects of the present invention to provide a panelboard or box construction containing a considerable number of suchdevicesand in which the arrangement is such that ready and easy accessvmay be had to the various elements, and at the same time they may beprotected from outside manipulation.

In practicing the invention, there is provided an insulating block whichnormally carries the ordinary socket for a fuse plug. The current iscaused to flow in said block through suitable arranged conductorsconnected respectively to the bus bar or feed line and to the individualcircuit. A gap is provided in the connection which is bridged by acontact member, the latter being yieldably held in place by a spring orthe like. Directly superimposed above said contact member is a set ofsockets into which a test plug may be introduced. The proportioning ofthe parts is such that when the test plug is first introduced, it formsa circuit in parallel to that passing through the contact member andthus insures against interruption of service. As the plug is pushedcompletely into its sockets, the free ends of the plug projectionsengage the contact member in such a manner as to break the circuittherethrough. Thereby, all of the current is now caused to pass throughthe test plug and the 55 meter or the like secured thereto.

(Cl. FZ5-183) In the accompanying drawings, constituting a part hereof,and in which like reference characters indicated like parts,

Fig. 1 is a fragmentary, top plan view or a box containing theimprovements of the present invention, some parts being broken away forclearness;

Fig. 2 is a fragmentary, vertical, cross-sectional view taken along theline 2-2 of Fig. 1;

Fig. 3 is a vertical, cross-sectional view taken l0 through one of theindividual devices constituting a part of the structure, of Fig. l; and

Fig. 4 is a transverse, cross-sectional view taken along the line 4-4 ofFig. 3.

The structure comprises a box I having cen- III trally located thereinand extending across the same a pair of partitions 2 and 3. Saidpartitions form a series of compartments 4, 5 and 6, the compartments land 6 being at the ends and being substantial duplicates of each other,and 20 the compartment 5 being of smaller extent and intended to provideaccess to fuse plugs. Covers 'I are provided for compartments 4 and 6,being hinged at 8 and having meter sockets 9 formed therein. Locks I0having operating handles II are provided on said covers opposite tohinges 8, whereby by means of latch I2' the covers I may be locked. Thecentral compartment 5 has a cover. I2 hinged at I3 and bearing lock I4having latch I5 to similarly lock the same against out- 30 side or undueinterference.

Within the box is provided two rows of test plugs IB and I6' in parallelrelationship, as most clearly shown in Fig. 1. Each of these devicescomprises an insulating body I'I of suitable ma- 5 terial, such as amolded phenol formaldehyde condensation product or the like, having anextension I8 at one end. In the latter there is provided a recessaligned with contact member I9 for the reception of a fuse plug. Aconducting 40 bar 20 is held in place by screw 2|, the head of which iswithin the socket and provides a second contact for the fuse plug.

The shell I9 is secured by screw 22 to conductor 23, terminating at oneside of gap 24 in block 45 I1. A second conductor 25 at the opposite endof gap 24 extends as shown in Fig. 3 to point 26, where it may beconnected to the house circuit.

As shown in Fig. 2 a pair of bus bars 21 is secured to bars 20 of theseries of devices I6 and I9 re- 50 spectively.

The gap 24 is bridged by contact member 28, having a pivot 29 centrallylocated therein and holding one end of spring 30 therein in such amanner that the connection is sufficiently loose u to allow contactmember 28 to readily and completely seat itself upon conductors 23 and25. 'Ihe opposite end of spring 30 is secured at 3| to conductor 23. Aninsulating member 32 is secured by pin 28 to the top face of contactmember 28 for a purpose to be later explained.

Openings 33 in the top of block I1 allow access to the gap 2l. There isinserted therein a pair of contact shells 34 which are connectedrespectively to conductors 23 and 25. A test plug 35 has dependentmembers 38 connected to conductors Within the same, said conductorsbeing encased in cable 31 and the extreme end thereof being secured at38 in meter socket 8, whereby a connection to a meter may be obtained.

In the operation of the device, assuming that the current is passingfrom bus bar 21 through bar 20, the fuse plug (not shown), conductor 23,contact member 28, conductor 25, and then to the house circuit, it isdesired to introduce a test meter into the same. Therefore, a meteris'inserted in meter socket 8 and projections 33 of test plug 35 areintroduced into openings 33. This causes a circuit to be formed fromconductor 23 through one projection 35 to the meter in socket 9 and backthrough the other projection 38, and thence to conductor 25. As the testplug 35 is brought into its final position, as shown in dotted lines inFig. 3, the extreme ends of projections 3B will contact with insulatingmember 32 and push contact member 28 away from conductors 23 and 25, asshown in Fig. 3, thus breaking the main circuit and compelling thecurrent to pass through the test meter. When the test is over, the testplug 35 may be removed. In the first movement thereof, the ends ofprojections 38 are taken out of contact with insulation 32, allowing theaction of spring 38 to cause contact member 28 to contact withconductors 23 and 25. Thereby, the parallel circuit is again formed andthere is no interruption of service. Upon the complete removal of testplug 35, the parallel circuit is broken but the current continueswithout interruption.

The present construction has a considerable number of advantages in thatit is simple and because of the form thereof, the operation becomesautomatic and no interruption of current takes place at any time. It isalso possible because of the present construction to arrange a largeseries of units in a single box so as to give great convenience ofoperation. Only a relatively small number of test meters are necessaryfor the successive testing of a large number of individually usedcircuits. None of the test meter connections are visible because of thelocked covers and therefore outsiders cannot determine which of thehouse circuits are being tested at any time. At the same time, thecentral compartment 5 being closed by an individual cover, allows readyaccess to the fuse plug sockets for the replacement of burnt out fusesand for other purposes. Because the individual blocks I1 are placed endto end with the projections I8 in contact. a very compact arrangement isthereby obtained.

If desired, there may be introduced into each individual circuit aswitch whereby the current may be cut of! altogether from an emptyapartment, for example. This may be accomplished by inserting a tumblerswitch or its equivalent between the bus bar and the test plug. Aconvenient arrangement is obtained by spacing test plugs I6 and I8' asubstantial distance apart and connecting a pair of switches betweensaid plugs and the bus bars, one switch to plug I8 and the other to plugl5'. The compartment 5 would be enlarged to accommodate both theswitches and fuse plugs.

Although I have described a test plug having two fingers or projections,one larger than the other to prevent reversal ofthe current through themeter, I may use a plug having only one projection. In such case, thereis provided an outer annular member fitting into socket 34, an innerannular insulating member, and a central conductor adapted to directlycontact with plate 28, which is suitably modified. By the term a pair ofprojections used in the claims, I include a construction, such asmentioned above. where both projections are in a single finger. Themeters may be placed within the compartments l and 8 instead of in thecovers thereof, and this is intended to be included in the language ofthe claims.

What I claim is:

1. A circuit testing device comprising an insulating base, a pair ofterminals adapted to be connected into an electrical circuit, a gapbetween said terminals, a contact member bridging said gap, means foryieldingly holding said member in contact closing position, a pair ofsockets in said base between said terminals, each of said sockets beingelectrically connected to its respective terminal, and a test plughaving a pair of conducting projections adapted to fit into saidsockets, whereby said plug upon being inserted first provides a parallelcircuit connection and thereafter breaks the connection of said contactmember.

2. A circuit testing device comprising an insulating base. a pair ofterminals adapted to be connected into an electrical circuit, a gapbetween said terminals, a contact member bridging said gap, means foryieldingly holding said member in contact closing position, a pair ofsockets in said base between said terminals, each of said sockets beingelectrically connected to its respective terminal, an insulating membersecured to said contact member and interposed between the latter andsaid sockets, and a test plug having a pair of conducting projectionsadapted to fit into said sockets, whereby said plug upon being insertedfirst provides a parallel circuit connection and thereafter breaks theconnection of said contact member.

3. A circuit testing device comprising an insulating base, a pair ofterminals adapted to be connected into an electrical circuit, a gapbetween said terminals, a contact member bridging said gap, means foryieldingly holding said member in contact closing position including aspring having one portion secured to said base and another portionsecured to thecentral part of said contact member, a pair of sockets insaid base between said terminals, each of said sockets beingelectrically connected to its respective terminal, and a test plughaving a pair of conducting projections adapted to ft into said sockets,whereby said plug upon being inserted first provides a parallel circuitconnection and thereafter breaks the connection of said contact member.

4. A circuit testing vdevice comprising an insulating base, a pair ofterminals adapted to be connected into an electrical circuit, a gapbetween said terminals, a contact member bridging said gap, means foryieldingly holding said member in contact closing position looselysecured thereto to permit positive seating thereof on said terminals, apair of sockets in said base between said terminals. each of saidsockets being eleclll trically connected to its respective terminal, anda test plug having a pair of conducting projections adapted to iit intosaid sockets, whereby said plug upon being inserted iirst provides aparallel circuit connection and thereafter breaks the connection of saidcontact member.

5. A circuit testing device comprising an insulating base, a pair ofterminals adapted to be connected into an electrical circuit, a gapbetween said terminals, a contact member bridging said gap, means foryieldingly holding said member in contact closing position, a pair ofsockets in said base between said terminals, each of said sockets beingelectrically connected to its respective terminal, a fuse plug socket insaid base adjacent one of said terminals and electrically connectedthereto, and a test plug having a pair of conducting projections adaptedto fit into said sockets, whereby said plug upon being inserted firstprovides a parallel circuit connection and thereafter breaks theconnection of said contact member.

6. A circuit testing board comprising a box having a plurality ofcompartments, a series of circuit testing plug socket devices inalignment therein, a bus bar electrically connected to said series, testmeter sockets adapted to hold meters on the cover of said box, saidcover being hinged, each of said devices having circuit interruptingmeans and a pair of test plug sockets for holding a test plug located inthe same compartment as said meter sockets, whereby when the cover isopened access is had so that a meter may be connected by means of saidtest plug to any one of said devicesl 7. A circuit testing boardcomprising a box having a plurality of compartments, a series of circuittesting plug socket devices in alignment therein, a bus bar electricallyconnected to said series, test meter sockets adapted to hold meters onthe cover of said box, said cover being hinged, each of said deviceshaving circuit interrupting means and a pair of test plug sockets forholding a test plug located in the same compartment as said metersockets, whereby when the cover is opened access is had so that a metermay be connected by means of said test plug to any one of said devices,each of said devices having a fuseplug socket all of which sockets arein alignment and are located in a separate compartment in said box.

8. A circuit testing board comprising a box, two series of circuittesting plug socket devices -therein, each of said devices havingcircuit interrupting meansand a pair of test plug sockets,

a fuse plug socket at one end of each oi said devices, said series ofdevices being in alignment with saidfuse sockets in adjacent relation, acentral compartment in said box, said devices being so arranged thatsaid fuse sockets lie in said compartment, two end compartments, the

test sockets of each series of said devices lyingV in their respectiveend compartments, test meter sockets adapted to hold meters in each endcompartment, a test plug adapted to be connected to a meter and to oneof said devices in each end compartment.

9. A circuit testing board comprising a box, two series of circuittesting plug socket devices therein, each of said devices having circuitinterrupting means and a p'air of test plug sockets. a fuse plug socketat one end of each of said devices, said series of devices being inalignment with said fuse sockets in adjacent relation, a centralcompartment in said box, said devices being so arranged that said fusesockets lie in said compartment, two end compartments, the test socketsof each series of said devices lying in their respective endcompartments, test meter sockets adapted to hold meters in each endcompartment, a test plug adapted to be connected to a meter and to oneof said devices in each end compartment, and an independently operablecover for each of said compartments.

10. A circuit testing device comprising an insulating base, a pair ofterminals adapted to be connected into an electrical circuit, a gapbetween said terminals, a contact member bridging said gap, means foryieldingly holding said member in contact closing position, a socket insaid base between said terminals and electrically connected to aterminal, and a test plug having conducting projections adapted to fitinto said socket, whereby said plug upon being inserted iirst provides aparallel circuit connection and thereafter breaks the connection of saidcontact member.

11. A circuit testing board comprising a box having a plurality ofcompartments, covers on said compartments, a series of circuit testingplug socket devices in alignment therein, a bus bar electricallyconnected to said series, test meter sockets adapted to hold meters insaid box, each of said devices having circuit interrupting means and atest plug socket for holding a test plug located in the same compartmentas said meter sockets, whereby when the cover is opened access is had sothat a meter may be connected by means of said test plug to any of saiddevices.

IRVING V. COLE. u

